1. Field of the Invention
The present invention relates to implantable penile prostheses, and in particular, it relates to penile prostheses which are selectively filled with a fluid by a pumping arrangement from a supply reservoir.
2. Description of the Prior Art
Sexual impotence caused by failure to achieve erection of the penis is a common problem. When the impotence is organic in origin, surgeons have attempted to duplicate the function of the erectile tissue (corpora cavernosa) in the penis by way of a surgically implanted prosthesis. The function of the prosthesis is to provide an artificial erection.
One type of prosthesis presently being used is a hydraulic type of prosthesis having generally tubular-shaped prosthetic members with extensible walls for implantation in the corpora cavernosa. The prosthesis is inflated by using a fluid drawn from a reservoir. As the prosthesis is inflated, the penis changes from a flaccid state to an erect state, mimicing normal erection. There are several prior art hydraulic prostheses for implantation in the corpora cavernosa. Several types of hydraulic prostheses are described in the following patents: Strauch et al U.S. Pat. No. 3,853,122, Uson U.S. Pat. No. 4,009,711, Finney et al U.S. Pat. No. 4,201,202, Yamanaka U.S. Pat. No. 4,235,227, Scott et al U.S. Pat. No. 4,224,934, Burton et al U.S. Pat. No. 4,267,829 and the Finney U.S. Pat. Nos. 4,318,396; 4,353,360 and 4,360,010. In addition, a PCT international published application submitted by Said Hakky having publication number WO 80/00302 shows a hydraulic prosthesis. The above mentioned patents disclose an implantable penile prosthesis having hydraulic prosthetis members that are supplied a fluid from a reservoir. The reservoir is made from a flexible material and is squeezed to pump fluid to enlarge the prosthetic members.
Two articles entitled "An Implantable Fluid Transfer System for Treatment of Impotence," in the Journal of Biomechanics by Kothari, Timm, Frohrib and Bradley, Vol. 5, November, 1972, pp. 567-570 and "Management of Erecticle Impotence, Use of Implantable Penile Prosthesis," in Urology by Scott, Bradley and Timm, Vol. II, No. 1, July 1973, pp. 80-82, describe a hydraulic penile prosthesis having two prosthetic members, a reservoir, a first squeezable bulb for pumping fluid from a reservoir into the prosthetic member, and a second squeezable bulb for pumping fluid from the prosthetic member back to the reservoir. The prosthesis described in the Kothari et al and the Scott et al articles, although a refinement of the manner of supplying fluid to the prosthetic member over previous devices, has a disadvantage that the user must differentiate between the first bulb and the second bulb through the skin.
The Buuck U.S. Pat. No. 3,954,102 describes a prosthesis having a pair of hydraulic prosthetic members, an elastomeric bulb implantable in the scrotal sac for inflating and deflating the prosthetic member and a reservoir. The bulb is squeezed through the user's skin to pump fluid from the reservoir to the prosthetic member. To deflate the prosthetic member, the device includes a bypass valve arrangement. The bypass valve arrangement has a ball that is seated at both ends so that a sealing action normally exists within the elastomeric bulb permitting pumping of the fluid from the reservoir to the prosthetic member. When the device is squeezed in the location of the bypass ball, the ball is unseated, permitting the fluid to bypass both check valves and return to the reservoir, deflating the prosthetic member. However, the device of the Buuck Patent is difficult to use since generally the pumping portion of the bulb is difficult to distinguish from the bypass portion by feel through the user's skin.